<template>
    <view class="viewport">
      <!-- 推荐封面 -->
      <view class="cover">
        <image :src="bannerPicture"></image>
      </view>
      <!-- tab栏 -->
      <view class="tabs">
        <text
          class="text"
          v-for="(item, index) in recommendList"
          :key="index"
          :class="{ active: index === activeIndex }"
          @tap="changeTabs(index)"
        >
          {{ item.title }}
        </text>
      </view>
  
      <!-- 列表内容 -->
      <scroll-view
        scroll-y
        class="scroll-view"
        @scrolltolower="handleScrolltolower"
        :key="index"
        v-for="(item, index) in recommendList"
        v-show="activeIndex === index"
      >
        <view class="goods">
          <navigator
            hover-class="none"
            class="navigator"
            v-for="goods in item.goodsItems.items"
            :key="goods.id"
            :url="`/pages/goods/index?id=${goods.id}`"
          >
            <image class="thumb" :src="goods.picture"></image>
            <view class="name ellipsis">{{ goods.name }}</view>
            <view class="price">
              <text class="symbol">¥</text>
              <text class="number">{{ goods.price }}</text>
            </view>
          </navigator>
        </view>
        <view class="loading">正在加载...</view>
      </scroll-view>
    </view>
  </template>

<script>
import { getHomeRecommend } from "@/api/home";
export default {
    data() {
    return {
      // 背景大图
      bannerPicture: "",
      // 当前显示的tab栏
      activeIndex: 0,
      // 列表数据
      recommendList: [],
    };
  },
 async  onLoad({type}){
      // type 上一个页面 传递过来的 数据
    // 标题和 接口的url地址 前端写死
    const urlMap = {
      1: { title: "特惠推荐", url: "/home/preference/mutli" },
      2: { title: "爆款推荐", url: "/home/inVogue/mutli" },
      3: { title: "一站买全", url: "/home/oneStop/mutli" },
      4: { title: "领券中心", url: "/home/new/mutli" }, // 后端未提供，暂用新鲜好物url
      5: { title: "新鲜好物", url: "/home/new/mutli" },
    };
     // 确定用户点击的是哪个数据
     this.currentItem = urlMap[type];
     // 分页 节流阀
     this.isLoading = false; // 没有人在发送请求
// 动态设置页面的标题
uni.setNavigationBarTitle({ title: this.currentItem.title });
// 发送请求获取数据 // 首次加载可以不携带参数  用默认的即可
    const res = await getHomeRecommend(this.currentItem.url)
    console.log(res);
    // 设置背景图
    this.bannerPicture =res.result.bannerPicture
    // 修改数据编程我们需要的样子
    this.recommendList =res.result.subTypes.map((v)=>({
        id :v.id,
        title:v.title,
        goodsItems:res.result.goodsItems[v.id]
    }))

   } ,
   methods:{
    changeTabs(index){
        this.activeIndex =index
    },
    async handleScrolltolower(){
        // 获取当前显示的tab项目的id
        const id = this.recommendList[this.activeIndex].id
        let  {page,pages,pageSize} = this.recommendList[this.activeIndex].goodsItems
        if (!this.isLoading&&page<pages) {
            this.isLoading = true;
            // 下一页数据
            page++
            const res =await getHomeRecommend(this.currentItem.url,{
                page,
                pageSize,
                subType:id
            })
            // 更新页码
            this.recommendList[this.activeIndex].goodsItems.page =res.result.goodsItems[id].page
            // 数组追加
            this.recommendList[this.activeIndex].goodsItems.items =[
            ...this.recommendList[this.activeIndex].goodsItems.items,
            ...res.result.goodsItems[id].items
            ]
            this.isLoading = false;
        }
    }
   }
};
</script>

<style lang="scss">
page {
  height: 100%;
  background-color: #f4f4f4;
}
.viewport {
  display: flex;
  flex-direction: column;
  height: 100%;
  padding: 180rpx 0 0;
  position: relative;
}
.cover {
  width: 750rpx;
  height: 225rpx;
  border-radius: 0 0 40rpx 40rpx;
  overflow: hidden;
  position: absolute;
  left: 0;
  top: 0;
}
.tabs {
  display: flex;
  justify-content: space-evenly;
  height: 100rpx;
  line-height: 90rpx;
  margin: 0 20rpx;
  font-size: 28rpx;
  border-radius: 10rpx;
  box-shadow: 0 4rpx 5rpx rgba(200, 200, 200, 0.3);
  color: #333;
  background-color: #fff;
  position: relative;
  z-index: 9;
  .text {
    margin: 0 20rpx;
    position: relative;
  }
  .active {
    &::after {
      content: "";
      width: 40rpx;
      height: 4rpx;
      transform: translate(-50%);
      background-color: #27ba9b;
      position: absolute;
      left: 50%;
      bottom: 24rpx;
    }
  }
}
.scroll-view {
  flex: 1;
  overflow: hidden;
}
.goods {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  padding: 0 20rpx 20rpx;
  .navigator {
    width: 345rpx;
    padding: 20rpx;
    margin-top: 20rpx;
    border-radius: 10rpx;
    background-color: #fff;
  }
  .thumb {
    width: 305rpx;
    height: 305rpx;
  }
  .name {
    height: 88rpx;
    font-size: 26rpx;
  }
  .price {
    line-height: 1;
    color: #cf4444;
    font-size: 30rpx;
  }
}
.goods .symbol,
.goods .decimal {
  font-size: 70%;
}
</style>